With the increasing consciousness of personal health and environmental protection, it becomes more and more common to use a gas detecting apparatus. For instance, after decoration of a room, people often use the gas detecting apparatus to detect the air quality in the room, so as to determine whether the content of harmful gas in the room exceeds a permissible standard, and whether the room is suitable for living. The prior gas detecting apparatus is generally a specialized one provided by a professional gas detection organization. It normally has a large size and is not convenient for carrying on, and its operation is quite complex. If one needs gas detection, she has to invite a skilled person from the professional gas detection organization to sample and analyze the gas to be detected by using the gas detecting apparatus so as to get the gas detection results. Because in the related art, there is no type of gas detecting apparatus that is potable and can be used conveniently by a consumer anywhere and anytime, people cannot detect the gas by themselves and cannot learn the concentration of harmful gas as well as the danger degree in the environment they are staying at real time.
Mobile terminals are widely used since they are portable and easy to use, but the prior mobile terminals generally only have a single function of communication, and people generally use them for talking and sending short messages. A mobile terminal with a function of gas detection warning has not arisen so far.